Portable radio receiver



Aug. 24, 1948. G. E. GUSTAFSON PORTABLE RADIO RECEIVER Filed March 11,1944 FIG. 3

INVENTOR GILBERT E. G usTAF soN b mm H .s ATTORNEY Patented Aug. 24,1948 stars PGRTAB'LE RADIQ RECEIVER Gilbert ill. 'Gustafson, RiverForest, 111., assignor to Illinois Zenith Radio Corporation, acorporation of Application March '11, 1944, Serial No. 526,095

2 Claims. 1

This invention relates to radio apparatus, and particularly to suchapparatus provided with a loop antenna arranged to be used with theapparatus either mounted on the apparatus or in positions remote fromthe apparatus.

Portable radio receivers have heretofore been provided with loopantennae which can be used either within the receiver case or housing,or in a 'locat-ion'remote from such case or housing, as, for example, onthe window "of a railroad car or other vehicle. Such an antenna whenvused within the receiver case or housing is much 'aifectedby proximityto metal portions of the receiver and, if the receivercase or housing ismade of metal, the an tenna is entirely useless when mounted inside ofthe housing.

It is a primary object of this invention to provide a loop antennamounted in connection with radio apparatus in new "and improved way,whereby it may be used either when fastened to the housing or at aposition remote from the apparatus housing, and when fastened to thehousing is substantially unaffected by metal parts of the apparatus.

Another object of the invention is to provide an improved antennamounting arrangement for such radio apparatus which is especially usefulwhen the housing for the apparatus is constructed primarily of metal orconductive materials.

It is a further object of this invention to provide such an improvedantenna arrangement for radio apparatus which can be readily carriedwhile the loop antenna and radio apparatus are in operation.

The features of the present invention which are believed to be novel areset forth with particularity in the appended claims. This inventionitself, both as to its organization and manner of operation, togetherwith further objects and advantages thereof, may best be understood byreferenoe to the following description taken in connection withtheaccompanying drawing in which:

Figure 1 illustrates a radio receiver incorporating this invention andarranged for operation with a loop antenna mounted on the window of ametal railroad car;

Fig. 2 shows the same receiver closed up and in inoperative conditionfor carrying; and

Figs. 3 and 4 are 'elevational views of the rear side of the loopantenna, before and after being arranged for support as shown in Fig. 1.

Figure 5 is an illustration of an operative element of the receiver ofFigure 1.

Figure 6' is a partial cross-sectional view of. a. portion of thestructure of Figure 4.

In Fig. 1, a radio receiver it having trapezoidalshaped ends as shown inFigures 1 and 2 is illustrated on the seat of a railroad car orautomobile. A door H, which normally encloses the front of the receiveris illustrated in an open position, in which it lies in a vertical planeabove the receiver iii. The front of the receiver ill, which is normallyenclosed by the doorll, has extending therefrom control knobs l2 for thetuning of the receiver and the volume control and on-ofi switchcombination, as well as the tuning dial l3, and is found in theapertured area it behind which the loud speaker is placed.

The door ii is formed of dielectric material, such as wood, fiber orplastic, audit is supported on the housing of the receiver ill byrelatively long armed metal hinge members it, which extend substantiallyat right angles to the door M, the hinge members it each having one ofits ends fastened to the normally upper portion (Fig. 2) of door l l andhaving its other end pivotally mounted on receiver ll). The hingemembers l5 are each insulated from other conducting portions of thereceiver l9, and are connected through leads iii to the radio frequencyinput terminals on the receiver chassis within the housing of receiverin. Within the door l l, the hinge members i 5 are respectivelyconnected to suitable conductors and to two snap fastener members ll andi8 mounted on the inner side of the door ll. That is, the

snap fasteners ll and it are on that side of the door ll adjacent thecontrol knob l2 when the door It is closed.

Snap fastener elements 3i! and 3E complementary to the snap fastenermembers ll and it on the door it are carried on one end of a relativelywide tape or web member l9 along the respective edges of which twoinsulated conductors extend. These two conductors are connected to suchcomplementary snap fastener elements 3i! and 3! at the one end of thetape !9, and at the other end of the tape it those two conductors arerespectively connected to snap fastening elements 29 and 2!, supportedon that other end of the tape. The same distance lies between the snapfastening elements 2!} and 2B and between the snap fastening elements lland i8, and likewise between the snap fastening elements 3% and 3| onthe tape H3 complementary with the snap fastenrnembers H and E8. Thesnap fastening membrs ill and M on the end of the tape is remote fromthe receiver it! are, as may be best seen in Figs. '3 and 4, arranged tosnap onto a pair of complementary snap fastener members 22 and 23, onaloop antenna structure 24. The loop antenna structure 24 comprises abody of dielectricai insulating material upon, or preferably within,which a loop antenna is arranged with the ends of the looped conductorconnected respectively to the snap fastener elements 22 and 23. The bodyof the antenna structure 24 carries, in addition to the snap fastenerelements 22 and 23 which act as electrical terminals for the loop,supporting snap fastener elements 25 which are suitably spaced to fastento complementary snap fastener elements 2E supported on the door ll ofthe receiver l0.

Suction cups 27, each having a snap fastener element complementary tothe snap fastener element 25 on the loop antenna structure 24, may besnapped onto the loop antenna structure to support it upon any smoothdielectric surface such as the window 28 of a metal or shielded vehiclewithin which the receiver l is disposed.

When the receiver is so arranged, with the antenna structure 24 mountedby means of suction cup 21 on a window 28 and connected through the tapewith the radio frequency terminals I! and 18 on the door H of thereceiver ill, the receiver may be operated :by means of the knobs E2,the antenna .24 being positioned for good reception of radio frequencyenergy in the shielded structure.

When the receiver is in a different location Where it is not surroundedby conductive walls such as are usually encountered in vehicles, theends of the tape is may be detached respectively from the antennastructure 24 and the radio frequency terminals I! and H! on the door II, and the antenna structure 24 may be fastened on the inside of thedoor H by snapping together the cooperating snap fastener elements 25and 26, and the cooperating radio frequency terminals I7, I8, 22 and 23.The tape [9 may be stowed in a suitable place within the housing of thereceiver 10.

When the loop antenna structure 24 is so supported on the inside of thedoor II, the receiver being in a position surrounded by conductingwalls, the loop structure 24 is in a favorable position for thereception of radio frequency energy, since the door H is of dielectricor insulating material, and since the door carries the loop structure 24at a substantial distance from any metal portion of the radio apparatuswithin the housing of the receiver Hi.

It may be desired to make the housing of the receiver in except door llof light metal, such as magnesium or aluminum, and in that case thepositioning of the antenna structure 24 upon the inside of the door H inits raised position is exceptionally desirable to maintain the antenna24 away from any shielding and damping effect which is otherwiseproduced by the conductive metal housing of the receiver in on the loopantenna. If the housing of the receiver in is made of metal, and if theloop is mounted on or within that metal housing, the pickup of radiofrequency energy would be so small as to be useless, and it is thenhighly desirable to mount the loop as described in accordance with thepresent invention.

When the loop antenna structure 24 is mounted in accordance with thisinvention on the door H, the only metal parts of the receiver In beingthose provided in connection with the radio apparatus carried within thehousing of the receiver, the pickup of radio frequency energy by theloop structure 24 is at least twice that obtained when the loop ismounted on or within the housing of the receiver 18 in the normalfashion and relatively near the metal chassis of the receiver.

When the loop antenna structure 24 is mounted on the inside of the doorII, as described, a handle 29 provided on the upper surface of thehousing of the receiver 10 is readily accessible for the purpose ofcarrying the receiver with the lid II in the open position, so that thereceiver may be thus carried while it is operating.

When it is desired to discontinue operation of the receiver, one of theknobs I2 is adjusted to deenergize the receiver and the door H is movedover the handle 29 and toward the front of the housing of the receiverl0 and downward to cover the knobs l2, where it may be locked inposition by suitable locking means. By the provision of the long armedhinge members l5, which are pivoted on the housing of the receiver H] atpoints on an axis extending substantially through the handle 29, thedoor ll clears the handle 29 readily. That is, the hinge members I5 aresufficiently long that theyclear the upper surface of the housing of thereceiver in by a distance such that the handle 29 may be provided ofrelatively large size for easy carrying of the receiver. This is sosince the hinge members l5 are pivotally mounted on the receiver at apoint substantially in the plane of the upper face of the receiver andat a point lying substantially midway between vertical substantiallyparallel faces of the receiver.

When it is desired to use the receiver Ill illustrated in Fig. 2 in itsclosed position, the door H is raised and pushed to its position shownin Fig. 1 back of the handle 29, where it is in stable equilibrium andwhere it lies in a substantially vertical plane a substantial distancebehind the plane of the control panel including the knobs l2 and thetuning dial i3 and speaker located behind apertured area l4. With thedoor H in that position, the set may be operated by the knobs 42, solong as it is in a position where it is not surrounded by a conductiveshielding wall such as in a train or automobile.

If the receiver in is to be used within an enclosure where someshielding is experienced, the loop structure 24 is unsnapped at the doorH and the tape l9 removed from the place where it is stored within thereceiver it. One end of the tape i 9 is snapped onto the snap fastenerelements or radio frequency terminals l'l and ill on the door 5 l, andthe other end of the tape is is snapped onto the snap fastening elementsforming the electrical loop terminals on the loop structure 24. Suctioncups 2? are removed from a position within the housing of receiver I0wherein they are stowed, and they are snapped on the snap fasteningelements 25 on the loop structure 24. The loop structure 24 is thenfastened by means of the suction cup 2'! to a smooth surface such as thewindow 28, whereupon the radio receiver l0 may be made to operate byadjustment of the knobs l2.

It is to be noted that when the structure 24 is mounted on a surfacesuch as the window 28 by means of a suction cup 21, the same side ispresented to the view of an operator of the receiver H as is presentedby the loop structure 24 when it is mounted on the door II. A suitablymodest and attractive design is applied to that side of the loopstructure 24, in keeping with the appearance of the remainder of thereceiver Ill. On the other side of the loop structure 26, as illustratedin Figs. 3 and d, a more elaborate design of an advertising nature maybe placed, that side being obsoured by the door I I when the loop 24 ismounted thereon, but being visible through the window 28 from outsidethe vehicle when the loop 24 is mounted on the window 28.

While particular embodiments of the present invention have been shownand described, it will be obvious to those skilled in the art thatchanges and modifications may be made without departing from thisinvention in its broader aspects, and, therefore, the aim in theappended claims is to cover all such changes and modifications as fallwithin the true spirit and scope of this invention.

I claim:

1. In radio apparatus comprising a case enclosing a radio circuit havingtwo terminals and a door closing at least a portion of one side of saidcase, the combination of long arm hinge members permanently fixedsubstantially perpendicularly to one edge of said door and permanentlysecured pivotally on an adjacent side of said case about an axis lyingsubstantially parallel to said one side of said case and substantiallymidway of said adjacent side of said case, a handle substantiallycentrally located on said adjacent side of said case, said door beingarranged to open on said hing members away from said case a distancesufficient to move over said handle to a position on the other side ofsaid handle from said one side of said case, a unitary loop antennastructure having snap fastening means connected in circuit therewith,snap fastening means complementary to said snap fastening means of saidantenna structure arranged on that side of said door adjacent said casewhen said door is closed, means for connecting said snap fastening meansof said door with said two terminals of the radio circuit through saidhinge members, and a flexible two conductor transmission line havingsnap fastening means on the ends thereof respectively complementary tosaid snap fastening means on said antenna structure and said snapfastening means on said door, said line being detachably connectedbetween said door and said antenna structure and providing connectionsthrough said snap fastening means, line, and hinge members between saidantenna structure and said radio circuit terminals, said two firstmentioned snap fastening means being arranged so that said antennastructure may be supported on said door and connected to said twoterminals by cooperation between said two first mentioned snap fasteningmeans when said line is detached from the door and antenna.

2. In radio apparatus comprising a case enclosing a radio circuit and adoor closing at least a portion of one side of said case, thecombination of long armed hinge members permanently fixed to said doorand permanently secured pivotally adjacent another side of said case ona line spaced a substantial distance from said one side of said case,said door being arranged to open upon said hinge members away from saidone side of said case and to move over said other side of said case to aposition removed from one side of said case, an antenna, means fordetachably securing said antenna on said door, said means comprisingcomplementary snap-fastening means on said door and said antenna, meansfor connecting said antenna with said radio circuit through saidsecuring means and said hinge members, means for electrically connectingsaid snap fastening means together whensaid antenna is detached fromsaid door thereby to connect said antenna with said radio circuit, andmeans for quickly attachably and detachably securing said antenna on asurface spaced from said apparatus, the last means having snap fasteningmeans complementary to said snap fastening means on said antenna therebyto secure said last securing means on said antenna after detachment ofsaid antenna from said door.

GILBERT E. GUSTAFSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 783,003 Westerbeck Feb. 21, 19051,093,110 Christopher Apr. 14, 1914 1,640,370 Asplund Aug. 30, 19271,809,028 Fanarjian June 9, 1931 1,901,808 Hammer Mar. 14, 19332,202,930 Steiner June 4, 1940 2,255,897 Rebori Sept. 16, 1941 2,295,191Adams Sept. 8, 1942 2,315,315 Cairnes Mar. 30, 1943 FOREIGN PATENTSNumber Country Date 79,094 Sweden Nov. 28, 1933

